Field of the Invention
The invention relates firstly to a composite pack, in particular a parallelepipedal cardboard/plastic composite pack for flowable products, having an opening region provided in the top of the pack which forms a pouring opening after it is cut through by an applied pouring element, the pouring element comprising a base body, a cutting element arranged movably therein, and a screw cap, the screw cap being used for first opening of the pack by actuating the cutting element and for reclosure, and the opening region having a weakened line in the composite and a hinge region, on which the part of the opening region formed after the weakened line is cut through is tilted into the interior of the pack and held there. The invention furthermore relates to a blank made of cardboard/plastic composite material for producing such a pack, and to a pouring element for use with such a pack.
Description of Related Art
Composite packs having pouring elements, which are also used for first opening, are known in practice in a wide variety of variants. The composite material comprises at least one carrier layer made of cardboard, and respectively polyethylene layers sealed on externally, which protects the cardboard against moisture. Since the thin PE films are highly extensible, it is generally not readily possible to apply pouring elements, which are provided with a cutting element, at an arbitrary position on the pack without prior introduction of weakened regions.
It is therefore known to prepare the cardboard/plastic composite packs in question in such a way that a weakened line is formed there, while being adapted to the geometry and size of the pouring element to be used, in order to achieve clean, easy and reliable cutting out of a part of the pack wall during first opening, so as to form the pouring opening. To this end, it is known to introduce so-called weakened lines into the outer layers of the pack material, which in conjunction with the cutting element ensure that easy, reliable and full separation takes place.
So that the cut-out part of the pack cannot interfere with the pouring process, it should on the one hand not be cut out fully and thus enter the product, and on the other hand it should not fold back and thus fully or partially close the pouring opening.
A composite pack of this type is known from EP 1 623 931 B1. In this case, the first time the screw cap is actuated (unscrewed), a cutting element arranged inside the pouring element is set in movement in such a way that it cuts a round pouring opening out of the composite material of the pack along a prepared weakened line. A projection extending into the circular weakened region ensures that the part cut out is not fully separated from the composite material, and it is simultaneously used as a hinge in order to tilt the cut-out part into the interior of the pack.
EP 1 399 366 B1 discloses a closure device with a piercing element, which is used for opening a composite pack according to the preamble of Claim 1. In this case, the opening line extends in a circle, the opening process being influenced by the choice of an offset angle α, so as to ensure that a region not yet cut through is folded to the side during opening, without the composite material being torn in this region.
It is also known to weaken the future pouring openings by stamping a hole into the cardboard before the lamination, this hole then being reclosed on both sides by the PE layer during the lamination (“prelaminated hole”). In this case, only the PE material remains to be cut out by the pourer. A disadvantage with this is that the partially cut-out part of the PE layers is not rigid, and therefore remains in the pack in an undefined way, so that problems may occur during the pouring process.
In order to overcome this problem, according to the teaching of EP 2 287 082 A1, the prelaminated hole is no longer formed circularly, but for example is formed as a “C”, in order to provide a material bridge that is as wide as possible, which allows the separated part to be tilted in a defined way into the interior of the pack and fixed there.
It has also already been proposed to use asymmetrical weakened lines, in which case the weakened line extends in a spiral and a material bridge which can be used as a hinge is therefore formed between the ends of the line (WO 2006/000881 A2).